function convert_uuencode(str) {
  //       discuss at: http://phpjs.org/functions/convert_uuencode/
  //      original by: Ole Vrijenhoek
  //      bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
  //      bugfixed by: Brett Zamir (http://brett-zamir.me)
  // reimplemented by: Ole Vrijenhoek
  //       depends on: is_scalar
  //        example 1: convert_uuencode("test\ntext text\r\n");
  //        returns 1: "0=&5S=`IT97AT('1E>'0-\"@``"

  var chr = function(c) {
    return String.fromCharCode(c);
  };

  if (!str || str === '') {
    return chr(0);
  } else if (!this.is_scalar(str)) {
    return false;
  }

  var c = 0,
    u = 0,
    i = 0,
    a = 0;
  var encoded = '',
    tmp1 = '',
    tmp2 = '',
    bytes = {};

  // divide string into chunks of 45 characters
  var chunk = function() {
    bytes = str.substr(u, 45);
    for (i in bytes) {
      bytes[i] = bytes[i].charCodeAt(0);
    }
    if (bytes.length != 0) {
      return bytes.length;
    } else {
      return 0;
    }
  };

  while (chunk() !== 0) {
    c = chunk();
    u += 45;

    // New line encoded data starts with number of bytes encoded.
    encoded += chr(c + 32);

    // Convert each char in bytes[] to a byte
    for (i in bytes) {
      tmp1 = bytes[i].charCodeAt(0)
        .toString(2);
      while (tmp1.length < 8) {
        tmp1 = '0' + tmp1;
      }
      tmp2 += tmp1;
    }

    while (tmp2.length % 6) {
      tmp2 = tmp2 + '0';
    }

    for (i = 0; i <= (tmp2.length / 6) - 1; i++) {
      tmp1 = tmp2.substr(a, 6);
      if (tmp1 == '000000') {
        encoded += chr(96);
      } else {
        encoded += chr(parseInt(tmp1, 2) + 32);
      }
      a += 6;
    }
    a = 0;
    tmp2 = '';
    encoded += '\n';
  }

  // Add termination characters
  encoded += chr(96) + '\n';

  return encoded;
}